Conduit



y 24, 1932- I M. CHRlSTlE 1,859,864

CONDUIT Filed June 18, 1930 INVENTOR LLEWELLYN M. CHRISTIE, OF PITTSBURGH,

Patented May 24, 1932 UNITED STATES PATENT OFFICE PENNSYLVANIA, ASSIGN OR TO NATIONAL or PENNSYLVANIA CON DUIT Application filed June 18,

This invention relates to conduit, and more particularly to conduit adapted for housing cables or wires, pneumatic tube systems, underground pipe lines and the like. It relates still more particularly to a conduit ofthe type comprising a. plurality of axially eX- tending portions connected together insuch manner that at least one of such portions may be removed topermit cables, wires and the like to be laid into the conduit, thus eliminat-' ing the necessity of drawing -the same through.

I Conduits of the type mentioned, generally known as trough conduits, are well known. An aim of the present invention is to improve such conduits by the provision of one in which the body or casing port-ion of the conduit and the top or cover portion are effectively secured or connected together, and also by the provision of means for effectively sealing the conduit so as to render it waterproof.

I provide a conduit comprising a plurality of axially extending portions connected together peripherally of the conduit, such portions being adapted to be interlocked, whereby to be positively held against outward displacement. I further provide a conduit comprising a hollowed casing member open at a portion of its periphery and a cover cooperating therewith for closing the open portion, the casing member and the cover being adapted to be interlocked whereby to be positively held against relative outward displacement.

In the accompanying drawings I have shown a present preferred embodiment of the invention, in which Figure 1 is an isometric view of a length of conduit; and

Figure 2 is a cross-sectional View of the conduit shown in Figure 1.

Referring more particularly to the drawings, reference numeral 2 designates generally a body or casing member of a conduit which is formed of generally U-shape and provided with a cavity 3 adapted to receive cables, wires, tubes, pipes and the like. The bottom of the member 2 is generally flattened,

as at 4, and the sides are flared somewhat out-.

1930. Serial No. 462,053.

wardly near the top, as at 5, and each is provl'ded internally of the member 2 with a seat or supporting portion 6 u on which is adapted to rest a top or cover The bottom of the cover 7 flat, as at 8, and is adapted to rest upon the opposltely disposed seat portions 6 of the member 2. The sides of the cover 7 are tapered downwardly and outwardly, as at 9, and the inner faces of the upper extremities of the sides of the member 2 are similarly tapered, as at 10. The taper of the cover and body member are shown in the drawings to be. substantially the same, although this is not essential.

After the cover has been put in place on the body or casing member of the conduit, sealing material such as cement 11 is adapted to be poured between the cover and the casing member. The sealing material not only seals the conduit and renders it substantially waterproof but also, by reason of the inclination of the lateral faces of the body member and cover,elfectively wedges or kevs the covonto the body whereby to tightly hold the cover in place and prevent the same from being lifted off.

As shown in the drawings, the width of the lower face of the cover 7 is very slightly lessthan the width of the top opening of the body member 2. This permits the cover to be put in place when the conduit is being assembled. It is not essential that the width of the cover be less than the width of the top opening of the body member because, on account of the taper of the upper extremities of the body member, the cover can be inserted by moving it angularly even though the width of the cover is substantially the same as the width of the top opening of the body member. By reason of the fact that the cover and body member are tapered as described, the cement or sealing material 11 poured in between the cover and body member serves upon hardening as a key or locking means to positively prevent removal, of the cover. If it is attempted to remove the cover the sealing material will be compressed by a wedging action between the cover and the body member and will resist relative movement thereof. In"

is substantially sealing material 11 is poured in,

pletingthe conduit.

"'embodiediwi'thin claims.

fact, it is not possible to lift out the cover without first breaking up the sealing material.

Although the invention is shown as applied to plane end conduit, it is equally applicable to hell and spigot conduit sections. When *plane end conduit sections are used they are adapted to abut one anotheraxially of. the conduit, and in order to insure proper alignment, holes 12 forthe reception of dowel pins are provided.

The body members of the respective conduit sections are adapted to be first laid in place as desired, whereupon the cables. wires, tubes, pipes or other devices may be laid in them. The necessityof drawing thecablcs orwires through the conduit is entirely eliminated. Further-more, the-conduit may be used for housing pipe lines by first laying the pipes in place and then pouring a waterproof compound orcement into the trough and around' -the pipes, thus. in effect, embedding the pipes in the cement or waterproof compound. The coveris laid in place and the thus coin- Although it is desirable to use a'scaling material such as cement for aiding in fastening'together the cover and body member of the conduit, various other materials may be used,-and, if desired, strips of suitable materialsuch as rubber, fabric or thelike may be in serted between the coverand body member to assist in or effect the desired seal and locking action. Preformed key means may be used in place of the cement 11, if desired, "althoughit is more diflicultto effect the sealing of the conduit when such means are utilized, particularly if a waterproof conduit is desired. 'The preformed keys serve equal- I claim:

1. A conduit comprising a trough portion providing a duct and having below its upper surface a pair of oppositely disposed substantially horizontal cover receiving surfaces, generally downwardly and outwardly and then generally upwardly extending surfaces into which said substantially horizontal cover receiving surfaces respectively merge, and. a

cover adapted'to he seatedupon said cover receiving surfaces. I

2. A conduit comprising a trough portion providing a duct and havlng below its upper surfacea pair of oppositely disposed cover receiving surfaces extending generally horizontally, then generally downwardly and outwardly, then generally upwardly and inwardly, and a tapered cover adapted'to be onedbetween said surfaces.

A conduit comprising a trough portion providing .a duct and having-below its upper surface a cover receiving recess the sides. .of which taper upwardly and inwardly, and a cover insertableinto such recess-by move- ,mcnt substantially in a plane perpendicular to the axis of the conduit, the sidesv of said cover when in place being adapted to be spaeedfrom and lying generallyparallel to the sides of the recess.

lriltespimony .whereofI have hereunto set .niv ant.

LLEVVELLYN M. CHRISTIE.

l'y as well as the poured cement to key the wise extend across the joints between the respective cover -1nembers. Thus the respective component members of the coniduit serve to strengthen the connections between the other component members.

Even though dowel pins between adjacent trough sectlons should be omltted or become displaced, the cover member extending across the joint maintains the integrity of the con- 'bers. The respective trough members like- *duit. 'This is true because of the key effect between the trough and-cover members.

"'While Irhave shown and described a pres- '7 ent preferred embodiment of the invention, it 7 to be understood that the same is not limf ited thereto but lmay .be otherwise variously the scopeof the following 

